I don't feel that the playing of rugby necessarily equates to violence. It is a full contact sport, but played within the rules it is the same as any sport.

Violence can be found in any sport, whether a contact sport or not, and is representative of the person, not the sport.

I also don't believe that the occupation of a person gives rise to their desire to play any particular sport to let off steam. Some people are happy with a glass of wine, or a game of chess. Again, this goes to the type of person, not the occupation.

You played rugby at school where the laws of the playground ultimately held sway. If you had played any other sport then the violence would have existed all the same, because you were playing with other children.